GFX-Display: Set backlight duty factor to 127 for DV10

BZ: 24890

From panel spec, we don't found exact saying about maximum value of backlight
duty, but per the debug resust, when set it to 127 instead of 255, it can work.

Change-Id: Ide08eb912f1e6e4882db4630c68ef181b815ed12
Signed-off-by: Geng Xiujun <xiujun.geng@intel.com>
Reviewed-on: http://android.intel.com:8080/36338
Reviewed-by: Ai, Ke <ke.ai@intel.com>
Reviewed-by: Xu, Randy <randy.xu@intel.com>
Reviewed-by: Tong, BoX <box.tong@intel.com>
Tested-by: Tong, BoX <box.tong@intel.com>
Reviewed-by: buildbot <buildbot@intel.com>
Tested-by: buildbot <buildbot@intel.com>

diff --git a/drivers/staging/mrst/drv/mdfld_dsi_output.c b/drivers/staging/mrst/drv/mdfld_dsi_output.c
index 6fe972c..81440c8 100755 (executable)
--- a/drivers/staging/mrst/drv/mdfld_dsi_output.c
+++ b/drivers/staging/mrst/drv/mdfld_dsi_output.c
@@ -287,7 +287,12 @@ void mdfld_dsi_brightness_control (struct drm_device *dev, int pipe, int level)
                duty_val = level + 1;
        }
 
-       #define BACKLIGHT_DUTY_FACTOR 255
+#if defined(CONFIG_SUPPORT_TOSHIBA_MIPI_LVDS_BRIDGE)
+#define BACKLIGHT_DUTY_FACTOR 127
+#else
+#define BACKLIGHT_DUTY_FACTOR 255
+#endif
+
        duty_val = level*BACKLIGHT_DUTY_FACTOR/MDFLD_DSI_BRIGHTNESS_MAX_LEVEL;
 
        PSB_DEBUG_ENTRY("[DISPLAY] %s: level is %d and duty = %x\n", __func__, level, duty_val);